Wall tie for concrete forms

ABSTRACT

A reusable wall tie for maintaining the correct spacing between the form walls of concrete forms includes a spreader for preventing the walls from collapsing inwardly and a tie rod for preventing the walls from spreading apart. The spreader has a tapered shank and a threaded stud extending from the small end of the shank. The stud fits through a hole drilled in one of the form walls prior to the erection of the other form wall. A nut threads over the stud and temporarily secures the spreader to the form wall such that the tapered shank projects inwardly therefrom. The other form wall is positioned against the large end of the tapered shank on the spreader, and the two walls are tied together by a tie rod which extends through the spreader. After concrete is poured between the walls and allowed to set, the spreader is dislodged from the concrete by striking the stud end with a mallet.

Elite States atet Farrow 5] Mar. 14, 1972 [54] WALL TIE FOR CONCRETEFORMS [21] Appl. No.: 33,309

[52] U.S.Cl .249/43, 249/216 Primary Examiner-J. Spencer OverholserAssistant Examiner-John S. Brown Attorney-Gravely, Lieder & Woodruff[57] ABSTRACT A reusable wall tie for maintaining the correct spacingbetween the form walls of concrete forms includes a spreader forpreventing the walls from collapsing inwardly and a tie rod forpreventing the walls from spreading apart. The spreader has a taperedshank and a threaded stud extending from the small end of the shank. Thestud fits through a hole drilled in one of the form walls prior to theerection of the other form wall. A nut threads over the stud andtemporarily secures the spreader to the form wall such that the taperedshank projects inwardly therefrom. The other form wall is positionedagainst the large end of the tapered shank on the spreader, and the twowalls are tied together by a tie rod which extends through the spreader.After concrete is poured between the walls and allowed to set, thespreader is dislodged from the concrete by striking the stud end with amallet.

6 Claims, 6 Drawing Figures PATENTEDMAR14 I972 WALL TIE FOR CONCRETEFORMS BACKGROUND OF THE INVENTION This invention relates in general toconcrete forms and more particularly to means for maintaining the properspacing between the walls of such forms.

It is common practice in the building construction industry to pourconcrete into forms constructed from large sheets of plywood which areheld together by numerous steel tie rods called wall ties. These wallties not only keep the opposed form walls from spreading, but they alsoprevent the walls from collapsing inwardly toward each other beforeconcrete is poured between them. Since the wall ties are relatively thinand serve a dual purpose, numerous tie rods are employed in a singleform. For example, in 100 feet of form, 8 feet high and 1 foot wide,approximately 250 wall ties are required to maintain the opposed formwalls in the proper spaced relation.

After the concrete has been poured into and set within the form, aworkman must go along the exterior surfaces of the form walls and clipoff the exposed ends of the wall ties to free the form walls from thehardened concrete. In view of the large numbers of wall ties inconventional forms and further in view of the fact that the workman mustclip both ends of each tie, the removal of forms by current proceduresis a time consuming and expensive process. Moreover under presentprocedures, wall ties for the most part remain embedded in the concretewall, and they therefore cannot be reused. Their ends furthermorepresent unsightly protrusions or blemishes along the wall.

SUMMARY OF THE INVENTION One of the principal objects of the presentinvention is to provide wall ties for holding opposed walls of aconcrete form in properly spaced relation. Another object is to providea wall tie which is easy to install and is only required in relativelysmall members. A further object is to provide a wall tie which is easilyremoved from the form and from the hardened concrete in the form so thatno unsightly protuberances remain in the concrete wall. An additionalobject is to provide a wall tie which is easily removed from the formand from the hardened concrete without damaging the wall tie so that itcan be reused. Still another object is to provide a wall tie spreaderwhich is initially embedded in the poured concrete, but is easilydislodged therefrom. These and other objects and advantages will becomeapparent hereinafter.

The present invention is embodied in a spreader for maintaining theproper spacing between concrete form walls. The spreader includes atapered shank and a stud at the small end of the shank. The studprojects through one of the form walls and is engaged by attaching meanswhich temporarily secures the spreader to that wall. The inventionfurther resides in a wall tie including the foregoing spreader and a tierod which extends longitudinally through the spreader and prevents theform walls from moving apart. The invention also consists in the partsand in the arrangements and combinations of parts hereinafter describedand claimed.

DESCRIPTION OF THE DRAWINGS In the accompanying drawings which form partof the specification and wherein like numerals refer to like partswherever they occur:

FIG. 1 is a perspective view of a concrete form held together with wallties constructed in accordance with and embodying the present invention;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a sectional view similar to FIG. 3, but showing the wall tiespreader being dislodged from the hardened concrete;

FIG. 5 is an exploded view of the wall tie spreader; and

FIG. 6 is a perspective view of a waler bracket used on the form.

DETAILED DESCRIPTION Referring now to the drawings, 2 designates aconcrete form which rests upon a footing 4 and includes a pair of spacedform walls 6 and 8 which are preferably composed of large sheets ofplywood. Backing each wall 6 and 8 and also forming part of the form 2are a plate 10 which extends along the footing 4 and a plurality ofstuds 12 which are set upon and extend upwardly from the plate 10 atequally spaced intervals. The studs 12 in turn are backed by horizontalwalers 14 which are secured to the studs by waler brackets 16. Thus, thestuds 12 and walers 14 serve as reinforcing members for the form walls 6and 8. Each of the brackets 16 comprises (FIG. 6) two pairs of spacedflanges 18 and 20 extending from a common connecting portion 22 andpresented at right angles to one another. The spacing between theflanges 18 is slightly greater than the width of the stud 12 to whichthe bracket 16 attaches, and this enables the flanges 18 to fit over thewall studs 12. The spacing between the flanges 20 is sufficient toenable them to receive the walers 14 to which the bracket 16 alsoattaches. The flanges 18 and 20 have apertures 24 through which nailsare driven for securing the brackets 16 to both the studs 12 and thewalers 14. Normally, the plates 10 are 2 inch X 4 inch timbers, thestuds 12 are 4 inch X 4 inch timbers, and the walers 14 are 4 inch X 6inch timbers.

To maintain the proper spacing between the opposed form walls 6 and 8, amultiplicity of wall ties 30 are connected between the opposed walls 6and 8 and portions of these wall ties 30 extend through the walers 14which back the studs 12. Thus, the wall ties 30 are disposed inhorizontally extending rows at the levels at which the walers 14 arepresented. Each wall tie 30 includes (FIG. 3) a spacer or spreader 32which prevents the opposed walls 6 and 8 from collapsing inwardly towardeach other, and a tie rod 34 which extends through the spreader 32 andalso through the walers 14 for preventing the walls 6 and 8 and thewalers 14 backing them from spreading apart.

More specifically, each spreader 32 includes (FIG. 5) a tapered shank 36having a radially extending lip 38 at its large diameter end. The endface of the lip 38 is continuous with the end face of the spreader 32and is squared off relative to the axis of the shank 36 so as to form anabutment 40 thereon. At its opposite or small diameter end the taperedshank 36 is also squared off in the formation of an abutment shoulder 42from which a threaded stud 44 projects along the axis of the shank 36.The threaded stud 44 is formed integral and coaxial with the taperedshank 36 and projects through a pair of washers 46 and 48. Its threadsare engaged by a nut 50.

When the spreader 32 is emplaced in the form 2 (FIG. 3), the threadedstud 44 extends through the form wall 6, and the washer 46 is positionedon one side of the wall 6 while the washer 48 is positioned on theopposite side. The nut 50 tightens down upon the washer 48 and when sotightened the washers 46 and 48 and the wall 6 are clamped between theshoulder 42 and the nut 50. This temporarily secures the spreader 32 tothe wall 6 with its tapered shank 36 projecting perpendicularly from theinside face thereof.

Finally the spacer 32 has an axially extending bore 52 which extendscompletely through the tapered shank 36 and threaded stud 44 and islarge enough in diameter to loosely receive the tie rod 34.

Each tie rod 34 is long enough to extend completely through the axiallyextending bore 52 of its corresponding spreader 32 as well as throughthe walers 14 located beyond each end of the spreader 32. At its one endthe tie rod 34 is provided with an enlarged head 54, while at itsopposite end it is provided with threads 56 which extend beyond thewaler 14 at that end. The threads 56 are engaged by a nut 58 whichtightens down against a small plate 60 located against the outer surfaceof the waler 14. Similarly, the head 54 bears against a plate 60 on theopposite waler 14. In lieu of the head 54, the tie rod 34 may at thatend be provided with threads 54 and a nut 58 also.

To construct a concrete wall by means of the form 2, the footing 4 isfirst poured in the conventional manner. Once the footing 4 has set, theplate for the form wall 6 is laid along the upper surface of the footing4 adjacent to one side thereof. Next the vertical flanges 18 of thewaler brackets 16 are fitted over and nailed to the studs 12 at thespacing selected for the walers 14. When the brackets 16 are correctlymounted, their common connecting portions 22 will bear against theoutwardly presented surfaces of the studs 12. Then with the walerbrackets 16 presented outwardly the studs 12 are raised and toenailed tothe plate 10 and at least some of the studs 12 are supported in anupstanding position by suitable bracing which extends away from thefooting 4. Thereafter the walers 14 are fitted between horizontalflanges of the waler brackets 16 and are nailed in place to secure thewalers 14 to the studs 12 at the desired vertical spacing.

Once the walers 14 are attached to the studs 12, the form wall 6, whichis normally composed of several large sheets of plywood, is positionedagainst the inwardly presented unobstructed surfaces of the studs 12 andis nailed thereto at a few locations. Next holes 62 (FIG. 3) largeenough to receive the threaded stud 44 on the spreader are drilled inthe form wall 6 opposite to the walers 14. To provide the same holespacing in the form wall 8 it is desirable to place that walltemporarily against the wall 6 and drill the holes 62 through both atthe same time. Thereafter holes 64 (FIG. 3) large enough to receive thetie rods 34 are drilled in the walers 14 which back the wall 6 and theseholes align with the holes 62 in the wall 6.

After the wall 6 has been erected and provided with the holes 62, thethreaded stud 44 of a spreader 32 is inserted through each hole 62. Ofcourse, to accomplish this the nut 50 must be removed, but the washer 46remains on the threaded stud 44 so that it is interposed between theabutment shoulder 42 at the end of the tapered shank 36 and the inwardlypresented surface of the wall 6. Then the other washer 48 and nut 50 arefitted over the end of the stud 44 exposed on the opposite or outer sideof the wall 6. In this connection, it should be noted that the length ofthe threaded studs 44 is somewhat less than the depth of the wall studs12 so that adequate clearance exists between the ends of the threadedstuds 44 and walers 14 for installation of the nuts 50 on the studs 44.Each nut 50 is tightened down against its respective washers 48 and thisfirmly, yet temporarily, positions the spreaders 32 on the wall 6 suchthat the tapered shanks 36 thereof project perpendicularly from theinwardly presented surface of the wall 6.

Once the spreaders 32 are emplaced the other form wall 8 is broughtagainst the abutments 40 on the tapered shanks 36 of those spreaders 32.Since the holes 62 were drilled in both walls 6 and 8 at the same time,the abutment 40 will extend around the peripheries of the holes 62 inthe wall 8 and the axial bores 52 through the spreaders 32 will alignwith those holes. Then the other plate 10 is laid on the upper surfaceof the footing 4 and more studs 12 are erected on that plate 10 in thesame manner. Similarly, walers 14 are secured along the outer sides ofthe studs 12 by waler brackets 16, and these walers 14 are locatedopposite to the holes 62 in the wall 8. The walers l4 backing the wall 8are likewise drilled to provide holes 64 which align with the holes 62in the wall 8 and are large enough in diameter to receive the tie rods34.

After the erection of the wall 8 and the studs 12 and walers 14 backingit, the tie rods 34 are passed through the aligned holes 64 and 62 inthe walers l4 and walls 6 and 8 as well as through the axial bores 52 inthe spreaders 32. The head 54 at one end of each tie rod 34 bearsagainst the adjacent waler 16 through the plate 60 which encircles thattie rod, whereas at the opposite end of the tie rod 34 the nut 50 isengaged with the threads 56 and tightened down against the oppositeplate 60 which in turn bears against the opposite waler 14.

Thus the tie rods 34 urge the opposed form walls 6 and 8 inwardly andthereby keep them from falling away from each other. The spreaders 32,on the other hand, by reason of the fact that they abut against theinwardly presented surfaces of the walls 6 and 8 at the washers 46 andthe abutments 40,

respectively, prevent the walls 6 and 8 from collapsing inwardly andfurthermore maintain the correct spacing between the walls 6 and 8 sothat those walls remain truely parallel.

After the form 2 has been erected in the foregoing manner, concrete ispoured between the walls 6 and 8 and allowed to set into a hardenedconcrete wall 66. Removing the form 2 from the wall 66 is a simpleprocedure. More specifically, the form 2 is stripped away from thepoured wall 66 by first removing the nuts 58 from the ends of the rods34 and then withdrawing the tie rods 34 completely from the spreaders 32as well as from the walls 6 and 8 and the walers 14 backing those walls.Since the tie rods 34 extend through the bores 52 in the spreaders 32,and are not embedded in the concrete, they are easily withdrawn from thepoured concrete wall 66. Then the studs 12 and walers 14 are removedfrom both form walls 6 and 8, and the wall 8 is further stripped awayleaving one surface of the poured concrete wall 66 exposed and the othersurface covered by the form wall 6. Next the nuts 50 which formally heldthe spreaders 30 in place, are threaded outwardly until their outer endfaces are presented slightly beyond the ends of the threaded studs 44,in which case the nuts 50 will still remain engaged with the studs 44.Then each nut 50 is struck with a wooden or hard rubber mallet, the blowbeing directed axially toward the large diameter end of the taperedshank 36 (FIG. 4). This dislodges the shank 36 from the set concrete andfrees it for removal from the opposite side of the concrete wall 66 oncethe nut 50 and washer 46 are removed.

After the spreader 32 is removed from the concrete wall 66, the ends ofthe transversely extending hole left by it are plugged with a quickdrying mortar such as POROX. The shallow recesses left in the wall 66 bythe washer 66 and lip 38 provide a greater surface area along which themortar adheres, and thus the ends of the holes formerly occupied by thespreader 32 are sealed, without leaving unsightly protrusions orblemishes on the wall.

Relatively few wall ties 30 are required to hold the form 2 togetherwhen compared with the number of conventional ties required to hold aform of equivalent size together. For example, in a form feet long, 8feet high, and 1 foot wide at the walls 6 and 8, 75 wall ties 30 arerequired, whereas 250 conventional wall ties are required for aconventional form the same size. This reduces the labor required toconstruct the form 2, resulting in a considerable saving to the user.

Moreover conventional wall ties remain embedded in the concrete, whereasthe wall tie 30 is completely withdrawn and can therefore be used again.This reusable feature of the wall ties 30 in the long run affords asizeable saving, notwithstanding the greater initial cost. In this samevein, the wall ties 30 are not clipped off on each side of the concretewall 66 as are conventional ties, and this not only represents a savingin labor, but it also eliminates unsightly protuberances projecting fromthe wall.

The form 2 may also be constructed with the studs 12 and walers 14reversed. In other words, the walers 14 may be placed directly againstthe walls 6 and 8 and backed with the studs 12. In such a constructionthe number of walers 14 would be increased and the number of studs 12decreased in comparison to the previously described construction. Alsothe tie rods 34 would extend through the outwardly spaced studs 12 ofsuch a construction instead of through the walers 14.

This invention is intended to cover all changes and modifications of theexample of the invention herein chosen for purposes of the disclosurewhich do not constitute departures from the spirit and scope oftheinvention.

What is claimed is:

1. A spreader for use in a concrete form having a pair of spaced wallswhich are held together by tie rods, said spreader comprising a taperedshank terminating at abutments which are positioned adjacent the opposedsurfaces of the walls for preventing the walls from moving toward eachother, a reduced stud extending from the shank and projecting beyond theabutment at the small end of the shank and through the wall adjacent towhich that abutment is positioned, removable attaching means engageablewith the stud for temporarily securing the spreader to the wall throughwhich the stud projects, and a bore extending through the shank and studfor accommodating the tie rod.

2. A spreader according to claim 1 wherein the tapered shank and studare disposed about a longitudinal axis for the spreader; and wherein thegreatest dimension of the stud taken normal to the longitudinal axis isless than the smallest dimension of the tapered shank taken normal tothe longitudinal axis.

3. A spreader according to claim 2 wherein the tapered shank is circularin cross section and the abutment at the small end of the shank is ashoulder.

4. A spreader according to claim 3 wherein the shank is provided with aradially projecting lip at its large end; and wherein the abutment atthe large end of the shank is formed in part on the lip.

5. A spreader according to claim 3 wherein the stud is provided withexternal threads; and wherein the removable attaching means is a nutwhich engages the threads and when tightened down causes the wallthrough which the stud extends to be clamped between the shoulder andthe nut whereby the tapered shank will project outwardly from that wall.

6. A spreader according to claim 5 wherein a washer is interposedbetween the shoulder and the wall through which the stud extends.

1. A spreader for use in a concrete form having a pair of spaced wallswhich are held together by tie rods, said spreader comprising a taperedshank terminating at abutments which are positioned adjacent the opposedsurfaces of the walls for preventing the walls from moving toward eachother, a reduced stud extending from the shank and projecting beyond theabutment at the small end of the shank and through the wall adjacent towhich that abutment is positioned, removeable attaching means engageablewith the stud for temporarily securing the spreader to the wall throughwhich the stud projects, and a bore extending through the shank and studfor accommodating the tie rod.
 2. A spreader according to claim 1wherein the tapered shank and stud are disposed about a longitudinalaxis for the spreader; and wherein the greatest dimension of the studtaken normal to the longitudinal axis is less than the smallestdimension of the tapered shank taken normal to the longitudinal axis. 3.A spreader according to claim 2 wherein the tapered shank is circular incross-section and the abutment at the small end of the shank is ashoulder.
 4. A spreader according to claim 3 wherein the shank isprovided with a radially projecting lip at its large end; and whereinthe abutment at the large end of the shank is formed in part on the lip.5. A spreader according to claim 3 wherein the stud is provided withexternal threads; and wherein the removable attaching means is a nutwhich engages the threads and when tightened down causes the wallthrough which the stud extends to be clamped between the shoulder andthe nut whereby the tapered shank will project outwardly from that wall.6. A spreader according to claim 5 wherein a washer is interposedbetween the shoulder and the wall through which the stud extends.